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Home >> Lexus >> 2003 >> SC 430 >> Repair and Diagnosis >> Body & Frame >> Door Locks >> Power Door Lock Control System - Diagnosis >> Key Lock-In Prevention Function Does Not Work Properly (Unlock Warning Switch Circuit) >> Inspection Procedure
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Inspection Procedure

  1. USE LEXUS HAND-HELD TESTER 
    1. NO: Go to step   3 
    2. YES: 
  2. READ VALUE OF LEXUS HAND-HELD TESTER 
    1. Check the transponder key ECU by the ECU data monitor.

      Standard: 

    Transponder key ECU (switch condition) 

    TRANSPONDER KEY ECU SWITCH CONDITION

    Item Condition Specified condition
    Key switch IG ON/Without key ON/OFF
    1. OK: GO TO FLOW CHART OR PROBLEM SYMPTOM TABLE (See  KEY LOCK-IN PREVENTION FUNCTION DOES NOT WORK PROPERLY (COURTESY LAMP SWITCH CIRCUIT)  ) 
    2. NG: GO TO NEXT STEP 
  3. INSPECT UNLOCK WARNING SWITCH ASSY 
    1. Check the key unlock warning switch continuity.
    KEY UNLOCK WARNING SWITCH CONTINUITY CONDITIONS

    Condition Tester connection Specified condition
    Switch OFF (Key removed) - No continuity
    Switch ON (Key set) 1 <--> 2 Continuity
    Fig 1: Inspecting Unlock Warning Switch Assy
    G03370917Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPLACE UNLOCK WARNING SWITCH ASSY 
    2. OK: GO TO FLOWCHART OR PROBLEM SYMPTOM TABLE (See  KEY LOCK-IN PREVENTION FUNCTION DOES NOT WORK PROPERLY (COURTESY LAMP SWITCH CIRCUIT)   )